1. Field of the Invention
The invention relates to a valve having a housing, a solenoid arranged in the housing a pin that can be moved by the solenoid, and a pot-shaped piston connected to the pin, wherein the piston has an injection-molded diaphragm as a base and the pin is connected to the diaphragm, and a spring that bears against the diaphragm.
2. Description of the Related Art
Valves are used inter alia as an overrun air recirculation valve on the turbocharger in motor vehicles to open up a bypass to the intake side during overrun operation, and are therefore known. To prevent excessive braking of the turbocharger and to ensure a rapid start-up, rapid opening and closing of the valve is an essential prerequisite. During the closing process in particular, an important aspect is the immediate closure by way of the placement of the piston on a valve seat. The valve seat is formed by the housing of the turbocharger, on which housing the valve is flange-mounted. As a consequence, the valve seat is not completely parallel to the piston, which would be necessary for rapid and above all tight closing. In order to ensure a secure closing process, the piston has to adapt to the valve seat. For this purpose, it is known to connect the pin to the diaphragm of the piston. It is known from DE 10 2013 214 594 A to arrange a sleeve in the center of the diaphragm to anchor the pin. The sleeve is pressed on or welded to the diaphragm. A disadvantage here is that the fastening of the sleeve to the diaphragm leads to weakening of the diaphragm, in particular with regard to the long-term stability of the connection. Furthermore, the diaphragm is stressed by the spring, which spring generates the closing force, especially due to lateral relative movements of the spring.